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J Dymecki

Publications and source records attributed to J Dymecki.

At least 19 recordsLinked to original sources
PubMed1997

Qualitative and quantitative analysis of locus coeruleus neurons in Parkinson's disease.

The analysis of qualitative changes in the locus coeruleus (LC) was performed on brains from 21 cases of Parkinson's disease. Eleven cases were selected for quantitative analysis of the loss of LC noradrenergic pigmented neurons. The qualitative studies revealed uneven dissemination of the noradrenergic cells loss of overall structure of the LC. Few preserved neurons showed degenerative changes. Extracellular neuromelanine granules, traces of dying neurons, were also observed. A weak astro- and microglia proliferation corresponded with neuronal loss. Lewy bodies were found in the LC in all cases. The quantitative analysis revealed that the average loss of adrenergic neurons in the LC accounts for about 70% in relation to the control group. The degenerative changes were observed in the whole LC, but they were most intensive in its caudal and next in the middle segment. The results suggest also that the degenerative process began in the middle segment and then it spread towards caudal segment of the LC as the stages of disease advanced.

Aged↗
PubMed1997

Development of human fetal substantia nigra grafts in the brain of non-immunosuppressed rats.

The survival of xenogenous tissue after transplantation to the brain of Wistar rats without immunosuppression was studied. Cell suspension was prepared from the ventral mesencephalon of human embryos 7-8 weeks of gestation, and injected either into the striatum or motor cortex of adult rats. After 1, 3, 7, 14 days and 1, 3, 6, 8 months the rats were sacrificed and the brains were processed for tyrosine hydroxylase (TH), glial fibrillary acidic protein (GFAP), ferritin immunocytochemistry and electron microscopy study. The intensity of inflammatory reaction of the host brain strongly affected the viability of grafted cells, the extend of GFAP and ferritin reactions in the tissue around the graft. Grafted human TH-positive neurons were found for 3 month survival only. After transplantation, we observed the grafted cell differentiation similar to that in normally developing mesencephalon. Six and eight months after transplantation glial cells prevailed in the grafts, while most neurons looked abnormal. An extensive bundles of myelinated fibers transpassing the intracortical transplants were seen. We are concluding that human mesencephalic cells can survive and develop in the brain of non-immunosuppressed rats.

Animals↗
PubMed1997

[The structural organization of suspension grafts of human embryonic midbrain in the rat brain].

Dynamics of survival, differentiation and migration of human fetal cells after their transplantation into the rat brain without immunosuppression was studied using routine histology, electron microscopy and immunocytochemistry. A cell suspension prepared from the ventral mesencephalon of human embryos 7-8 weeks of gestation was injected into the striatum of rats-recipients. The graft development depends on the intensity of immune reaction. Under a weak reaction, the viability and differentiation of human embryo cells in the rat brain were observed within the three months of the experiment. The grafted cells conserve their mediator specificity, some of them being seen to migrate into the host (rat) tissue beyond the graft. In the transplant neuropil various types of cell contacts were observed, including synapses. The described method makes its possible to study the human nervous tissue histogenesis in an abnormal environment.

Animals↗
PubMed1997

Quantitative study of pathological forms of astroglia in Wilson's disease.

The number and distribution of Alzheimer type I and II cells (Alz I and II) as well as Opalski cells (Opl) were estimated in chosen brain regions of seven autopsied cases with Wilson's disease (WD). The authors of this study focused especially on the question whether the kind and intensity of astrocytes is linked to the clinical form of the disease and to the intensity of brain damage. Alz I and II cells were counted by the use of the HE method, whereas the number of Opl cells was calculated using the PAS method. The study revealed that among the three types of cells the number of Alz II cells was the highest and that of Alz I cells was the lowest. The distributional patterns of these three types of cells were different. Alz I cells were found mainly in the putamen. Alz II cells were observed diffusely, although they occurred in different numbers in the whole brain. The highest number of Opl cells was found in the putamen. Alz I cells were found only in the neurological type of the disease. The highest number of Alz II cells was seen in the hepatic type of the disease, whereas the highest number of Opl cells was observed in the neurological "mixed" forms. Moreover, intensity of tissue damage with presence of necroses was greatest in neurological WD. In the hepatic type dispersed areas of status spongiosus were observed, without presence of necroses. Our study revealed that the type and amount of the pathological astroglia may correlate both with the clinical form of WD and intensity of tissue damage. Alz II cells seem to be a characteristic feature of the early stage of astroglial response to the pathogenic factor whereas Alz I and Opl cells occur in WD only in the advanced stage of tissue damage.

Adolescent↗
PubMed1997

Fractal estimation of the senile brain atrophy.

The paper presents an attempt to fractal analysis of senile brain changes. The differences of atrophy velocity in the white and gray matter can be noticed via fractal dimension according to the described one layer approximate model. The young (34 years) and old (82 years) brains are examined and compared.

Adult↗
PubMed1996

Major histocompatibility complex class I expression on neurons in subacute sclerosing panencephalitis and experimental subacute measles encephalitis.

Lack of major histocompatibility class I antigens on neurons has been implicated as a possible mechanism for viral persistence in the brain since these antigens are required for cytotoxic T-lymphocyte recognition of infected cells. In subacute sclerosing panencephalitis (SSPE), measles virus (MV) persists in neurons, resulting in a fatal chronic infection. MHC class I mRNA expression was examined in formalin-fixed brain tissue from 6 SSPE patients by in situ hybridization. In addition MHC class I protein expression in MV-infected neurons was examined in experimental Subacute Measles Encephalitis (SME) by double immunohistochemistry. MHC class I mRNA expression was found to be upregulated in SSPE tissues studied, and in 5 out of 6 cases the expression was definitively seen on neurons. The percentage of neurons expressing MHC class I mRNA ranged between 20 to 84% in infected areas. There was no correlation between the degree of infection and expression of MHC class I molecules on neurons. Importantly, the number of neurons co-expressing MHC class I and MV antigens was markedly low, varying between 2 to 8%. Similar results were obtained in SME where 20 to 30% of the neurons expressed MHC class I but <8% co-expressed MHC class I and MV antigens. Perivascular infiltrating cells in the infected regions in SME expressed IFNgamma immunoreactivity. The results suggest that MV may not be directly involved in the induction of MHC class I on neurons and that cytokines such as IFNgamma may play an important role. Furthermore, the paucity of neurons co-expressing MHC class I and MV antigens in SSPE and SME suggests that such cells are either rapidly cleared by cytotoxic T lymphocytes (CTL), or, alternatively, lack of co-expression of MHC class I on MV infected neurons favors MV persistence in these cells by escaping CTL recognition.

Adult↗
PubMed1996

Changes in dopaminergic neurons of the mesocorticolimbic system in Parkinson's disease.

The qualitative analysis of changes in major nuclei (n. paranigralis left and right, n. interfascicularis) of the mesocorticolimbic system (ventral tegmental area-VTA) was carried out on 25 cases with Parkinson's disease (PD). The cellular depletion with insignificant gliosis without the presence of macrophages was found. In addition, numerous extracellular melanin nodules being the remnants of broken dopaminergic neurons were found. The presence of Lewy bodies observed in all cases confirms the diagnosis of idiopathic Parkinson's disease. The morphometric analysis performed on selected long-lasting 7 PD cases and 6 controls showed that cellular depletion in n. paranigralis and in n. interfascicularis accounts for 42% and 62%, respectively in relation to controls. The number of melanin nodules grows with the age in the control group. While in the group of PD cases the number of nodules in VTA declines with the disease duration. It may indicate that the factor which damages melanin neurons also exerts a destructive effect on extracellular melanin.

Age Factors↗
PubMed1996

Evaluation of survival and maturation of cryopreserved dopaminergic fetal cells transplanted into rat striatum and an analysis of the host brain reaction to graft.

A fetal, cryopreserved ventral mesencephalic rat tissue was transplanted into striatum of healthy adult rats. A stereotactic apparatus was used for transplantation of solid tissue blocks. The survival of transplanted dopaminergic cells in rat striatum was evaluated by means of histological and immunocytochemical methods (TH - thyrosine hydrolase) 1, 3, 7, 14, and 21 days after transplantation. The cellular reaction of the host to graft and to sham-lesion was examined. Glial fibrillary acidic protein (GFAP) was used for the visualization of astroglial reaction and ferritin for microglia. It was found that fetal cells of cryopreserved rat ventral mesencephalon transplanted into adult rat striatum survive though, in a small number. Cellular reactions of the host to both graft of dopaminergic cells and sham-lesion are similar to glial scar and are nonspecific.

Animals↗
PubMed1996

Adult schizophrenic-like variant of adrenoleukodystrophy.

A 35-year-old man died after 30 months following the onset of the disease. There was a history of changes in his mental condition, including disturbances of behavior as well as the evidence of progressing dementia. The patient revealed gait disturbances and finally became bed ridden. Bizarre behavior and changes of mood with concurrent growing irritability which predominated during the course of disease, may explain the initial diagnosis of schizophrenia. Then cerebellar and spastic movement disorders leading to paraparesis and sphincters disturbances developed. Clinical symptoms of adrenal failure were not found apart from episodes of arterial pressure fall. After two years a magnetic resonance imaging (MRI) revealed an extensive diffuse demyelinative process in white matter of cerebral and cerebellar hemispheres. Activity of lysosomal enzymes was normal. A general autopsy revealed atrophy of adrenal cortex and the presence of ballooned cells with striated cytoplasm in the reticular and fasciculate zones. Neuropathological examination revealed an extensive demyelination of white matter in cerebral and cerebellar hemispheres and of the long paths of the brain stem, corresponding to changes in MRI examination. Within demyelination areas damage of axons and diffuse cellular and fibrous gliosis were found as well as perivascular lymphocytic infiltrations with the presence of strong PAS (+) and Sudan (+) macrophages. Immunocytochemical reactions with HAM-56 and RCA1 in macrophages were positive. Electron microscopy examination revealed lamellar inclusions in cytoplasm of macrophages. Similar structures were present in the lysosomes of astrocytes. Morphological examination of adrenal glands as well as morphological and ultrastructural study of the brain allowed us to diagnose the cerebral form of adrenoleukodystrophy (ALD). Topography and character of the brain changes seems to be in keeping with a rare schizophrenic-like variant of ALD with progressive dementia. Abnormal plasma profile and increased VLCFA concentration in the patient's 13-year-old daughter confirm the ALD diagnosis.

Adrenoleukodystrophy↗
PubMed1995

Primitive neuroectodermal tumor (PNET). A case report.

The authors present a case of relatively rare tumor of the central nervous system (CNS) in a 19-year-old female, who died 18 months after the first manifestation of meningismus, increased intracranial pressure and secondary hydrocephalus. Brain autopsy revealed abundant neoplastic infiltrations, which spread through the subarachnoid space. Neoplastic infiltrations were also present in the third ventricle and in a form of small subependymal nodules along the whole ventricular system. The microscopical examination showed that neoplasm consisted of small cells, which formed neuroblastic Homer Wright rosettes. Immunohistochemical studies (for synaptophysin, chromogranin A, GFAP, vimentin) together with morphology and localization of neoplasm suggested diagnosis of primitive neuroectodermal tumor (PNET) that spread mainly in the leptomeninges and caused obliteration of subarachnoid space.

Adult↗
PubMed1994

[Mossbauer spectroscopy of iron in substantia nigra in Parkinson disease and controls].

Mössbauer spectroscopy was used to study iron content, its redox state and binding sites in substantia nigra from parkinsonian and control brains. Measurements performed on fresh frozen samples demonstrated the presence of ferric iron only, both in disease and control. We found no difference in the total amount of iron in substantia nigra between the disease and control. Mössbauer spectra observed at 4.1 K in fresh frozen samples were different from those obtained in formalin fixed samples. In the fresh frozen samples only ferritin like iron was observed, whereas in the formalin fixed samples also non-ferritin iron was detected. It seems that in formalin fixed brains, during years, iron is released from ferritin and bound to an iron chelator or formalin.

Aged↗
PubMed1994

[The application of graphic (visual) databases in neurology and neuropathology].

The possibilities and principles of creation in Windows environment of visual databases are described which could be used for elaboration of multimedial encyclopedia of selected nosological entities. Such databases are particularly important in education making possible finding of data and their relative comparison. The method of organization of "files" using standard programmes of Windows packs and the method of application of the technique of image coding for forms of symbolic icons are presented. Examples of graphic bases of neurological and neuropathological data evolved in Windows environment using professional application programmes (framing and retouching of images in graphic editors, coding of icons of macroinstruction of reading of information introduced into the relating visual database of the analysed cases.

Brain Diseases↗
PubMed1992

[Transplantation of fetal dopaminergic cells in Parkinson disease].

Four patients with severe form of Parkinson's disease received transplantation of fetal dopaminergic cells into the caput of the caudate nucleus. The operation was done by an original method using a device designed specially for this purpose. In all cases the duration of the disease was 10 to 15 years, and the predominating signs were tremor, bradykinesia, and markedly pronounced side effects of the treatment (on-off syndrome and involuntary movements). One patients died 5 weeks after the operation. Autopsy demonstrated good survival of the transplanted cells with good integration with the brain of the recipient and traces of positive immunocytochemical reaction for tyrosine hydroxylase. In the other patients a significant clinical improvement was noted after the operation, with reduced intensity of parkinsonian symptomatology, shortening of the duration of the off phase, improved motor ability and reduced intensity of the involuntary movements. The longest follow-up was 24 months.

Brain Tissue Transplantation↗
PubMed1990

Development of vessels in the foetal cortical transplant depending on the place of grafting in the rat brain.

Formation of new blood vessels within the graft is crucial for the survival of brain grafts. Moreover, it must occur rapidly to prevent ischaemic changes in the grafted neurons. A study was made of the development of the vascular system in the foetal cortical grafts depending on the place of grafting in the rat brain. Pieces of neocortical tissue from an 18-day old rat foetus were transplanted into the lateral ventricle, the striatum or the corpus callosum of 2 months old Wistar rats. The vascular system of the graft was visualized from coronal sections of the brain by means of Pickworth's technique 3, 7, 14 and 28 days after transplantation. After 3 days the vessels in the graft were absent. After 7 days the vessel pattern was poor and very simple and after 14 days the vessels formed large number of branches in the graft. After 28 days the pattern of the vascular network in the graft was similar to that of the vessels of the host brain. The size and branching of the vessels showed considerable variations depending on the localization of the graft.

Animals↗
PubMed1990

Intrastriatal grafts of adrenal medulla in hemiparkinsonian rats--ultrastructural study.

The aim of the study was to investigate the ultrastructure of the right striatum after intrastriatal adrenal medulla grafts in Wistar rats with a 6-OHDA unilateral lesion of the compact part of the right substantia nigra (SN). 12 adult rats were investigated. Two rats were intact, 2 received a sham SN-lesion. Ungerstedt's rotational test confirmed a significant lateral SN-lesion in all the animals. Two weeks after the SN lesion small samples of the adrenal medulla of 2-month old Wistar rats were prepared (0.5 mm3) and implanted stereotaxically into the middle-paraventricular region of the right striatum. The animals were perfused with 2.5% glutaraldehyd according to the following patern: 2--after 1 week of survival, 2--after 3 weeks, 2--after 6 weeks, and 2--after 3 months. 10 samples of ca 1 mm3 were taken from 3 regions of the right striatum (1) the region of the graft, (2) the region in the neighbourhood of the graft, (3) tissue at a long distance from the transplant. Macroscopic observation showed granulomatous-like tissue at the place of the implantation of the graft after 1 week of survival. After 3 weeks and later only the evacuated cavity was observed instead of the graft. A routine electron microscopic procedure was used to expose the material in a JEM 100 B electron microscope. The study of the ultrastructure indicated many leucocytes and microglia cells in the region of the graft as well as features of destruction of the adrenal medulla cells in the rats perfused 1 and 3 weeks after transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Medulla↗
PubMed1989

Postmortem detection of measles virus in non-neural tissues in subacute sclerosing panencephalitis.

Subacute sclerosing panencephalitis, a rare, progressive, fatal central nervous system disease of children, is caused by measles virus. Clinical signs occur months to several years after recovery from acute measles infection. It is not known where the virus persists while the disease is inapparent. Involvement of organs outside the central nervous system has rarely been documented. To search for possible peripheral reservoirs of measles virus we used in situ hybridization to probe for measles virus RNA and immunocytochemical studies to localize measles virus antigens ina variety of organs taken at autopsy from confirmed cases of subacute sclerosing panencephalitis. Seven of 9 cadavers were found to contain measles virus RNA or antigens, or both, in at least one location outside the central nervous system. These sites included lymphoid organs such as thymus, spleen, lymph nodes, and tonsil, suggesting a role for lymphocytes in disease pathogenesis. Virus was also detected in kidney, lung, and glandular tissues such as pancreas, adrenal, and pituitary. These reservoirs may provide the antigenic stimulus leading to the elevated response characteristic for subacute sclerosing panencephalitis.

Adolescent↗